As a result of some of the discussion in this thread, and some other threads that reference it, I made some additional measurements in the High Display Quality mode to determine the camera settings at which when focusing, the display quality briefly (fraction of a second) changes from High Display Quality to Standard Display Quality and then back to High Display Quality (I will call that Model High), and when focusing EVF display quality is locked into Standard Display Quality (Mode Standard). I edited table 1 in the post Page 3, #X as a result of the additional measurements. That revised table is also shown below.
The measurements were done as described in the earlier post. A Siemens star was observed through the EVF to make it clearly visible when the EVF display quality changed. I varied the Shutter Speed (SS), ISO, F/#, and illumination of the Siemens Star to determine what camera settings operated in Mode High and which operated in Mode Standard. I found that only the SS and ISO control EVF Display Quality. The F/# and Illumination of the scene, and consequently the EVF brightness, do not matter. The transition from Mode High to Mode Standard occurs when ISO*SS=4.
This result surprises me. I have no good explanation for it. Regardless, the discussions in this thread and others are wrong. That includes my original suggestion that it had something to do with DOF.
I did not measure how the update rate of the EVF may change, only how the resolution is changing. It is clear that when the SS gets to be long it is no longer possible to maintain even 60fps, but when the transition to lower EVF update rates occur and what the rates may be has not been measured.
Dec 19, 2024 at 08:32 PM
Previous versions of dclark's message #16710883 « A1 EVF resolution -- theoretical vs actual »
